"There were phone conversations with her, from this office, from the Helena Police Department, just prior to her death," he said. "So we're relatively certain of the time when she became deceased. It's a terrible thing to have happen, but we will work to find out what did happen. We'll cooperate with Spokane County , that's where we believe that the death occurred. But that's got to be confirmed by cell phone records."

Person of interest

After the call, an Idaho license plate reader notified authorities that the car had crossed into the city of Post Falls, the affiliate reported. Authorities used cell phone records to determine the car was heading toward Spokane.

Authorities did not release a cause of death, but said it is believed to be a homicide, according to the affiliate.

A GoFundMe page created after her death says Maze was on her way back from visiting her mother when she was abducted.

"We as a community will come together in this horrific time for the Maze family," the page says. "We need to do whatever it takes to make things easier for the family to grieve. Proceeds will go to helping to defray service expenses for this genuinely beautiful soul."

At first, authorities had said they have a person of interest, but a law enforcement official later told CNN that's no longer the case.

"There were earlier reports of a possible person of interest and the investigation found those reports are false," the official said.

Local FBI officials said the case is under investigation, but declined to provide details.

"The FBI Salt Lake City field office, along with the Lewis & Clark County Sheriff's Office in Montana, continue to investigate the death," said Sandra E. Barker of the FBI.

"This remains an active investigation and no further comment will be made at this time."